1. Field of the Invention
The present invention embodies an apparatus and method for exterior surface cleansing and outer boundary layer cooling a product through the utilization of a liquid coolant bath enclosed within a pressure vessel and wherein the product to be treated is introduced into and withdrawn from the interior of the pressure vessel through vapor lock structure including transfer chambers closable from the ambient atmosphere and the atmosphere within the pressure vessel and which may be vacuumed, selectively, to ambient atmosphere and the atmosphere within the pressure vessel above the liquid coolant level therein. The utilization of closable transfer chambers enables the utilization of a low boiling point coolant liquid with extremely low loss of that coolant liquid.
2. Description of Related Art
My prior U.S. Pat. No. 3,774,524, dated Nov. 27, 1973, discloses a closed pressure vessel into which a product to be treated may be introduced through vapor lock structure and in which the product being treated may be surface cleansed and outer boundary layer cooled. However, the apparatus disclosed in my above noted prior patent relies upon heater structure to cause coolant liquid remaining on the exterior surfaces of the product being treated, after removal of the product from the coolant liquid, to vaporize the coolant liquid on the surface of the product and thereby requires the utilization of higher capacity condensor structure within the pressure vessel to condense the vaporized bath liquid for return to the liquid bath. In addition, the vapor lock structure disclosed in my prior patent is not operative to maintain an appreciable pressure differential between the exterior and interior of the associated pressure vessel.